Enhanced and synthetic vision technologies (and even a combination of the two) promise to make flying on small- and medium-size aircraft safer.
When large airliners approach an airport for a landing, a combination of radio signals and high-intensity lighting shows the pilot exactly where the runway is, even at night or in fog. But millions of people a year fly on smaller commercial planes, many private, that do not have such technology. The pilots of those craft must rely on less sophisticated instruments, along with their cockpit window view during landing, a situation that can be fatal in bad weather. In 2011 alone four such commercial jets crashed into terrain or an obstacle, killing 140 passengers and crew, according to avionics-maker Honeywell and aerospace research firm Ascend. The accidents are known as “controlled flight into terrain.”
Landings could be safer if new navigation displays featuring nighttime infrared imaging and 3-D graphics that accurately portray an aircraft’s surroundings become standard equipment on smaller commercial and private planes. In addition to the potential safety benefits, Gulfstream, Bombardier and other makers of small and midsize business jets are also learning that the same technology can save time and money by keeping flights on schedule even in the face of weather that would normally require runway circling or flight rerouting.
The new technology, which this writer observed firsthand during a recent test flight (see video below), actually combines and leapfrogs two earlier technologies only recently being installed on smaller commercial craft. Synthetic vision systems (SVSs) use terrain data culled from actual flights and stored in a database to create a 3-D graphical interface (think Windows or Mac OS) on a screen in front of the pilot and co-pilot, enabling them to see a digital model of their surroundings even when their vision is obscured by darkness or clouds. SVSs also include information about the location of airports and runways, to help guide pilots until they can establish visual contact with their landing destination.
“The primary purpose of SVS is to provide pilots with situational awareness—where the aircraft is, in relation to the terrain,” says Randy Bailey, lead aerospace engineer for flight deck interface technologies in NASA’s Aviation Safety Program at the agency’s Langley Research Center in Hampton, Va. Situational awareness is an issue primarily for pilots of lower-end aircraft that do not have the autopilot or automated landing systems of high-end corporate jets or jumbo airliners. NASA has been studying SVS since the mid 1990s as part of a larger aviation safety program aimed at devising ways of reducing accidents in which a normally functioning aircraft slams into the ground, water or an obstacle.
Enhanced vision systems (EVSs) use infrared cameras located on or near the aircraft’s nose to enable nighttime vision on the pilot’s screen. EVS has gotten strong backing by the Federal Aviation Administration. According to FAA rules, by the time pilots descend to within about 60 meters of the ground they must be able to see the runway—or at least the runway lights at night or in cloudy conditions—in order to land their aircraft. But recently the FAA has made exceptions for EVS-equipped aircraft. Even if a pilot cannot see the runway or its lights at 60 meters, he is allowed to continue descending using the EVS until he gets to an altitude of about 30 meters. At that point, if he can see the runway or lights with his own eyes (not via EVS), he can land. Otherwise, he has to abort and take another approach, or circle and wait for the sky to clear. If most planes had this capability, more landings would occur first time and fewer planes would remain in the sky burning extra fuel.
Only about 1,000 aircraft are equipped with EVS today, and probably only three-to-four times as many SVS-equipped aircraft are in the air, Bailey says. Other aircraft in the same class do not have either system because the technology is expensive, yet these aircraft are the ones that often have the controlled-flight-into-terrain crashes.
By the end of February NASA will release the results of its latest commercial aviation safety research, which will analyze, among other things, the impact of pilot disorientation. Bailey says he cannot share specifics about the report before its release, but he does say, “Loss of control is diminishing, but unfortunately loss of state awareness, whether it’s [fatigue] or attitude awareness, is not where it should be, and we’re looking at potential technology interventions that might improve aviation safety.”
Read more . . .
Bookmark this page for “combined vision systems” and check back regularly as these articles update on a very frequent basis. The view is set to “news”. Try clicking on “video” and “2” for more articles.